1. Field of the Invention
The invention relates to a ventilator cap, preferably made of plastic, for ventilation of roofs in the ridge, hip or arris area, with a fastening area, with an edge area and with an intermediate area connecting the fastening area and the edge area with one another, in which the intermediate area exhibits air passage openings and the edge area exhibits, on the roof side, an elastically flexible sealing element extending over the length of the cap, and the sealing element has the structure of a fine-fiber brush with a carrier part and a plurality of elastic brush fibers arranged in a packing that is at least as flowtight as possible.
2. Description of Related Art
Ventilator caps of the above-mentioned type for ventilation of roofs have been known for quite a long time. For better ventilation of a roof cover, ventilator caps are placed in the ridge area of a roof to avoid possible damage from moisture formation. Ventilated roof covers generally have an inside shell, an outside shell and a ventilated roofing space. While the inside shell is basically used only for thermal insulation, the outside shell of the ventilated roof cover provides protection against weather. The outside shell must be able to deflect the precipitate moisture in a ridge-to-gutter direction, and is subject to especially extensive stresses caused by temperature. The ventilated space separates the inside and outside shells and is used to dissipate the construction moisture and the use moisture. The ventilation of the roofing space is, i.a., dependent on the cross section and the shape of the air gap, the cross section and the shape of the air openings, and the flow-impeding design components in the gap. The air entry or air exit openings for such a roof cover are generally provided in the gutter and ridge area.
Ventilator caps of the type placed in the ridge area assure a good ventilation of the roofing space and the dissipation of moisture. However, the placement of ventilator caps in the ridge area of a roof is problematical, since the air openings or air gaps existing in the ridge area between the ventilator cap and the roof cover have to be sectioned off in a watertight and snowtight manner, and the gaps to be sectioned off in the ridge area exhibit pronounced interval differences and sharp-edged transitions.
From German Gebrauchsmuster (Utility Model) DE-GM 89 13 744, which served as the starting point for the invention, ventilator caps are known that have sealing elements, placed on their edge area, in the form of fine-fiber brushes. The fine-fiber brushes have a plurality of elastic brush fibers, placed in at least as flowtight a packing as possible, which adapt without problems to the most varied gap shapes, especially also to sharp-edged transitions. In general, the brush fibers are made of polypropylene or nylon and exhibit a resilience, so that independently of the type of roofing material, the brush fibers lie against the corresponding transitions or against the roofing material.
The successful method of operation, i.e., the tightness of the ventilator caps provided with these sealing elements, diminishes under the continual influence of the weather conditions. The brush fibers exposed to solar radiation, especially UV radiation, and considerable temperature differences, can become embrittled, lose their resilience and break off easily, thereby reducing the packing density, so that the sealing function of such a sealing element, designed as a fine-fiber brush, is no longer sufficiently assured. In this way, rainwater or windborne snow can pass through the fine-fiber brush into the ventilation spaces of the roof cover, by which the moisture within the ventilated roof space increases.